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How to Read Call Numbers: Basics

Call Numbers

More on LC Call Numbers

Want to know more? View the full Library of Congress Classification Outline to see the LC tables that categorize the system by subject. They can be used to find the specific classification for your area of interest.

How to Read a Library of Congress Call Number

The UWSP Library uses the Library of Congress (LC) classification system to shelve most books. The classification system is designed to group library materials of similar subject concentration together.

The Library of Congress call number system is an alpha-numeric system. To read the call number, simply note the first letter or letters of the call number. "LA" would be shelved before "LB", "LC" before "LD", etc. Numbers follow the initial letter or letters. These numbers are read as whole numbers. A call number of "LA2" will be shelved before "LA4."


Here is a sample of how to read call numbers line by line:

How to Read Call Numbers